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Description: C. xinguensis are from the Rio Xingu Estado, Mato Grosso area of Brazil. Base colour grey, dark spots cover the body down below the level of the lateral line. Lower body and belly region plain grey. On close inspection spots can be seen on the dorsal and pectoral fin spines, caudal fin also has light spotting. Size 3.5 – 4cm.

Breeding Tank & Maintenance: Tank 18"x 8"x 8" with a small glass trough 8"x 2"x 2" placed to one side of the tank. This contained silver sand and planted with Indian Fern. Filtration: Air-driven sponge plus box filter filled with ceramic rings and a small amount of coral gravel to stabilise the pH of 6.5.

Feeding: I try to feed my fish at least twice daily with a good varied diet consisting of the following, Tetra Prima, frozen bloodworm/ black mosquito larvae and live grindal worms.

Preparation to Breed (Stage 1)
I didn’t stick rigidly to Kristian’s plan but used the basics and I started by reducing the water level by 10% every two days until the volume of water had been reduced by 50%. By this time the plants were just below water level. I also reduced the amount of feeding, some days no food at all. Air flow into the filters also reduced to a very slow flow. These conditions were maintained for the next 21 days (no water changes were carried out during this period.)

Stage 2:
I began reversing the process by adding fresh water, same pH and temperature values at the rate of 10% every two days. Feeding and filtration was also increased at the same time until the tank was back to normal. I again increased the feeding along with air supply to the filters giving even more water movement to the tank in an attempt to simulate nature during the rainy/flood season.Seven days later I checked water parameters, 73F/23C, pH5.8. I decided to carry out a 50% water change using water of 50F/10C, pH6.9. Once tank had settled the parameters were 61F/16C, pH6.4. The tank was then left alone to let things happen, if they were going to happen.

Spawning:
First eggs appeared five days later on the bottom of the tank. I decided to leave them in the hope of more to come. The following day I removed the six eggs and placed them in a 4" cube show tank as I feared the adults may be egg eaters (I soon discovered that my fears were unfounded). C. xinguensis eggs are very small, less than 2mm in size, sticky to the touch. Initially light sandy colour turning to dark tan during the 4 –5 days it took them to hatch (73F/23C). The following day there were two more eggs on the floor of the tank, while I was picking those up I brushed against the Indian Fern and more eggs fell from the plant leaves. Inspecting the plants I discovered over 40 eggs sticking to the underside of the leaves, some single eggs, some pairs but never anymore than two eggs together on the same leaf. Unfortunately 60% of the eggs were white and consequently proved to be infertile. What I did discover while rooting about with the plants were fry darting around the plant trough, proving the adults do not eat either eggs or fry.

Fry: When the eggs hatch the fry are a grey ball with a tail, 2mm total length. Day 2 they were free swimming. Feeding for the first two days with diluted Liqufry, followed on day three with microworm culture. Very soon they were eating newly hatched brine shrimp, fed little and often. 50% water changes were carried out daily using water from the breeding tank. Five days old the fry were starting to develop some speckling across the face and head. Seven days old the spots were over the face and down their back, they now resembled Corydoras catfish. At this stage the fry were transferred from the 4" hatching tank to a 7" cube with a sponge filter. Also added in this tank a piece of weighted Indian Fern, this provided refuge for the fry. As they progress they will be moved to a larger tank. The original fry were removed from the parents tank, within ten days more fry, approximately two days old, were siphoned out by accident while doing a water change. Any further fry in the parents tank will be left there. These will be monitored as to their progress, comparing them with the 25 fry that were removed as either eggs or fry.

Updated January 2001
The above fry all did well some were past on to friends sold to one or two local aquatic shops and some were even sold at fish auctions to the true aquarists who attend the shows / auctions. I was also awarded a First Time Bred & Shown Certificate by The Federation of Scottish Aquarist Societies for breeding these Corydoras catfish. The original 5 adult fish were past on to Allan James [Scotcat] who also has had some success in breeding them, the fry that I kept were left in the same tank since April 1999 and were given no special treatment, they were just left to grow up while I tried to breed some other species of Corydoras, with some success I may say, in fact I have bred 14 other species of Cory's since I first bred C. xinguensis. Yes I did say since I first bred them because what were the fry are now producing fry of their own, not that I have done anything special to get them to breed I just happened to spot some small fish in the tank, I say small fish not fry because they had all the markings of the adult fish but were only about a third of their size. This may help prove that F1 fish are easier to breed than wild fish or is it just sheer luck?

Reference: Kristian Adolfsson “Dry and rainy season periods in the tank”  This article also written for Paisley & District Aquarist Society, Allan James at Scotcat www.scotcat.com & Catfish Study Group plus Steve Miles at Catfish Corner

Photo Credit: © Ian Fuller @